Safety-catch for elevator-doors.



No. 759,485. PATBNTBD MAY 10,1904.

' G. F. STEVENS.

SAFETY CATCH FOR ELEVATOR DOORS;

APPLIUATION FILED AUG, 14, 1903. 4

N0 MODEL.

In vevzioen- C. Fifi'fe Mew-es v Patented May 10, 1904.

UNITED STATES PATENT OFFICE.

CHARLES F. STEVENS, OF WORCESTER, MASSACHUSETTS.

SAFETY-CATCH FOR ELEVATOR-DOORS.

SPECIFICATION forming part of Letters Patent No. 759,485, dated May 10,1904:. Application filed August 14, 1903. :Serial No. 169,422. (Nomodel.)

To (all whom it may concern:

Be it known that I, CHARLES F. STEvnNs, a citizen of the United States,residing at Worcester, in the county of Worcester and State ofMassachusetts, have invented a new and useful Safety-Catch forElevator-Doors, of which the following is a specification.

This invention relates to an improved construction for controlling thedoors or gates which open into elevator-wells.

The especial object of this invention is to provide a strong, simple,and efliciont locking mechanism which will prevent an elevator door orgate from being opened or raised ex cept at a time when the elevator-caris opposite the landing.

To these ends this invention consists of the locking-catch and of thecombinations of parts therewith, as hereinafter described, and moreparticularly pointed out in the claims at the end of this specification.

In the accompanying-drawings, Figure 1 is a side view, partly inscction,of suflicient parts of an elevator-car and an elevator-door toillus- ,trate the application of my invention thereto. Fig. 2 is aperspective View of the swinging latch forming part of the safety-catchconstructed according to this invention. Fig. 3 is a fragmentarysectional view thereof. Fig. 4; is a detail view illustrating theapplication of a safety-catch constructed according to this invention toan elevator-gate; and Fig. 5 is a perspective view of the cam foroperating the pivoted latch.

A large proportion of the accidents which happen in the use of passengerand freight elevators arise from persons attempting to entor theelevator-wells at times when the elevator-cars are not at the landing.Accidents of this kind are particularly liable to happen in the use ofhotel or other elevators Where the elevator is permitted to be operatedby a number of different people.

The especial object of my present invention is to prevent accidents ofthis class by providing simple and eflicient means for locking theelevator doors or gates, so that they cannot be opened except at suchtimes as the elevator-car is standing directly or nearly opposite thedoor. To accomplish these objects, a

safety-catch for an elevator door or gate constructed according to thisinvention comprises a latch or swinging piece, which is pivotallymounted substantially at its lower inside cornor in such position thatit will engage the door or gate and lock the same by gravity. Extendingdown from the swinging piece or latch is a spring-arm whichis-preferably pro: vided with a small roller to be engaged by a cam orreleasing plate which travels with the elevator-car. The lower end ofthe pivoted piece is preferably inclined or cut at an angle and isprovided with a set-screw which acts as a stop to limit the swingingmovement thereof. Extending from the latch or swinging piece is a guidestrip or linger which is engaged by the leading edge of the door or gateto permit the same to close past the catch, so that the gate or doorwill not be locked in opened position.

Referring to the drawings for a detail description of an apparatusconstructed according to my invention, A designates a portion of anordinary elevator-car which may be operated by a plunger B or otherconnections. The elevator-car A, as herein illustrated, runs past afloor F, and the opening from the floor F into the elevator-well isnormally closed by the door ID.

The safety catch or lock which I provide for cooperating with thedoor 1) comprises a hinge piece or casting 10, which may be fastened byscrews to the floor F. Pivotally mounted on a pin 11 in cars extendingup from the hinge-piece 10 is a swinging piece or latch 12. The pivot ofthe swinging piece or latch 12, as illustrated most clearly in Fig. 3,is located substantially at the lower inner corner thereof, so that saidlatch or swinging piece will be turned by gravity to engage behind thedoor D, as illustrated in Fig. 1. A clearance permitting the latch orswinging piece 12 to turn is provided by beveling or cutting off thelower end thereof at an angle, illustrated in Fig. 3, and the motion ofthe swinging piece or latch 12 may be limited by a small set-screw 13.Fastened onto the swinging piece or latch 12 and extending downtherefrom is a spring operating-arm 14., preferably having a roller 15journalcd at its lower end. The elevator-car A is provided with anoperating plate or cam 16, which may be fastened on a block 17 inposition to cooperate with and turn the latch from its operativeposition when the elevator-car is opposite the landing.

In the use of an apparatus as thus constructed when the parts occupytheir normal position as illustrated in Fig. 1, the swinging piece orlatch 12 engages behind the edge of the door D and forms an efiicientlock for holding the door in its closed or normal position, except at atime when the car is opposite the landing, and by employing anoperating-arm 1 1 of spring material the flexibility of said arm willpermit a proper opera-- tion even when the operating plate or cam on theelevator-car is not set to an absolutely accurate position. In thisconstruction also the operating-arm 14 will engage the hinge-piece 10 tolimit the motion of the swinging piece or latch 12, so that the centerof gravity thereof can never be thrown to the opposite side of itspivot.

In order to prevent the safety device from interfering with the shuttingor closing of the elevator-door, even when the elevator-car is not atthe landing, the swinging piece or latch 12 is provided with a curvedreleasingplate 18, which will permit the, leading edge of the door toturn the latch out of the way when the door is to be closed.

Whena safety-catch constructed according to this invention is to beemployed for controlling an elevator-gate, the parts may be arranged asillustrated in Fig. 4:. As shown in this figure, the swinging piece 12is provided with a detent or tooth 19, which will engage with andcooperate with an inwardlyprojecting tooth 21, carried by the gate G,and extending up from the pivoted piece 12 I may employ a curved plate20 for permitting the gate to be closed.

I am aware that numerous changes may be made by those who are skilled inthe art in applying my safety-catches to different elevatorconstructions. I do not wish, therefore, to be limited to the forms Ihave herein shown and described; but

What I do claim, and desire to secure by Letters Patent of the UnitedStates, is

1. As an article of manufacture, asafetycatch for elevator doors orgates comprising a hinge-piece located at the edge of a floor or landingwith a catch-plate pivoted substantially at one corner thereof in thehinge-piece, the pivotal point of the catch-plate being located so thatsaid catch-plate will normally turn by gravity to engage theelevator-door, and a light releasing-arm extending from the catch-plateto the other side of the pivot thereof in position to be engaged andoperated by the elevator-car, and also serving by engagement with thehinge piece to limit the extent to which the catch-plate can be turned,said parts being combined to form a gravity-operated lock for anelevator-door, substantially as described.

2. As an article of manufacture, a safetycatch for elevator doors orgates, comprising a hinge-piece, a swinging piece pivoted substantiallyat one of its corners in the hingepiece, a spring-releasing plateextending from the swinging piece, said parts being combined so that thecenter of gravity of the swinging piece will be kept at one side of itspivot.

3. As an article of manufacture, a safetycatch for elevator doors orgates, comprising a hinge-piece, a swinging plate pivoted substantiallyat one corner in the hinge-piece, a releasing-arm extending from theswinging plate in position to be engaged by an elevator door or gate topermit the same to be closed, a spring operating-arm extending down fromthe swinging plate and having a roller at its lower end and adapted toyield to permit the parts to operate when inaccurately adjusted and aset-screw for limiting the normal position of the swinging plate.

In testimony whereof I have hereunto set my hand in the presence of twosubscribing witnesses.

CHARLES E. STEVENS.

